Large computer networks, such as Wide Area Networks (WAN) or Internet backbone systems often incorporate various types of network devices (nodes) and network protocols. For example, for Synchronous Optical Network (SONET) systems, most communication between transport nodes uses the OSI (Open System Interconnection) over the DCC routing protocol to establish and route traffic between two nodes. The OSI model is a layered framework for distributed processing and networking in a multi-vendor environment. The OSI environment includes data communication protocols to manage data movement among network nodes and uses application-oriented protocols to ensure that once the data is transferred, it can be understood and processed by an application process. Typically, the overall system environment for large-scale networks use node manufacturer's proprietary software and services to fulfill distributed processing requirements. This type of network system redirects data from internal processes to the network interface.
Under the OSI model, functionally similar protocols are grouped into seven layers. These layers are: the physical layer, data link layer, network layer, transport layer, session layer, presentation layer, and application layer, with each layer providing services to the layer above it. The physical, link, and network layers are network dependent and use data communication protocols to control communication between two network nodes. The application, presentation, and session layers are application oriented and use protocols that let end user application interact using services offered by each node's local operating system. The transport layer uses services provided by the network dependent lower layers to provide the application oriented layers with a messaging service that is independent of the network.
In general, SONET networks use the TL-1 (Transport Layer 1) standard to communicate network management commands to the shelf. The TL-1 standard uses a particular type of address, called a Transport Identifier (TID) address, to address different nodes in the network. Typically, software is often used to map TID address received in a TL-1 command to addresses used by the OSI stack. Typical SONET systems using Bellcore/Telcordia equipment, have a special application called Terminal identification Address Resolution Protocol (TARP) that is used to map TID addresses to Network Service Access Point (NSAP) addresses used by the OSI stack. The Network Service Access Point is the point at which OSI Network Service is made available to a transport layer entity.
With ever increasing use of network communications, such as the Internet, usage for the IP stack increases. To support this increased demand, systems engineers have begun implementing systems for supporting IP over the Data Communications Channel (DCC), instead of the OSI stack. Most SONET Data Communications Channel is allocated for line data communication and is a 192-kbps message-based channel (using DCC in the section overhead) that is typically used for alarms, maintenance, control, monitoring, administration and communication needs between two section terminating nodes. The use of IP over DCC allows IP commands to be transported to any resident or remote network element on the SONET ring. Current systems, however, generally do not provide efficient mechanisms to provide TID to IP mapping over DCC. Although manual address mapping for gateway devices may be available, such manual methods are highly cumbersome, time-consuming, and prone to errors.
What is needed, therefore, is a system that automatically and efficiently maps TID addresses received within TL-1 messages to IP addresses over DCC for SONET networks.